Helm, who has held a number of high-profile marketing roles in his career, is thought to have left of his own accord, to launch a consultancy called Triniti Marketing.
Helm was responsible for a team of 23 marketers in his role at Mars, in which he oversaw Pedigree, Whiskas, Sheba, Cesar and Catsan. During his tenure, he launched Whiskas brand offshoot, Whiskas Simply.
Prior to his time at Mars Petcare, he was acting marketing director at Bear Nibbles, where he helped launch the environmentally conscious brand.
Before that, he was marketing director at Innocent Drinks, from January 2007 to June 2008.
Previously, he had been a brand controller at Nestlé Brands, between 1998 and 2007, where he headed up the marketing for Nestlé cereal and bars and repositioned the Nestlé cereal portfolio, which includes Cheerios, Shredded Wheat and Shreddies.
Mars was unavailable for comment.
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